VOSviewer map and network files
VOSviewer map and network files are tab-delimited text files for storing a network. A map file contains information about the items in a network. A network file contains information about the links between items.
Map and network files have multiple columns, separated by a tab, or alternatively by a comma or semicolon. Viewing and editing these files can best be done using spreadsheet software such as MS Excel.
VOSviewer map files
A VOSviewer map file contains information about the items in a network. Items are characterized by attributes. Each column in a map file corresponds with an attribute. Except for the first line, each line in a map file corresponds with an item. The first line is a header line that designates for each column the attribute represented by that column.
A map file may include the following columns:
| Header | Description |
|---|---|
| id | ID of an item. |
| label | Label of an item. |
| description | Description of an item. A description may include HTML formatting. |
| url | URL of an item. |
| x | Horizontal coordinate of an item. |
| y | Vertical coordinate of an item. |
| cluster | Cluster to which an item belongs. A cluster is represented by an integer between 1 and 1000. |
| weight<...> | Weight of an item. A weight is a non-negative number. |
| score<...> | Score of an item. |
If the label of an item contains a comma or semicolon, the label needs to be enclosed within double quotes. The same applies to the description of an item.
A map file may include multiple weight<...> columns. In the header of a weight<...> column, ... needs to be replaced by a label. For example, a map file may include a weight<Links> column, a weight<Documents> column, and a weight<Citations> column. In the same way, a map file may include multiple score<...> columns.
VOSviewer network files
A VOSviewer network file contains information about the links between items in a network. Each line in a network file corresponds with a link. A network file has two or three columns. The first two columns contain the IDs of pairs of items that are connected by a link. The third column contains the strength of a link, indicated by a positive number. If there are only two columns, all links have a strength of 1.
If a network file contains multiple links between the same pair of items, VOSviewer Online will merge these links into a single combined link. The strength of the combined link will be equal to the sum of the strengths of the individual links.
Example
This is an example of a VOSviewer map file:
id label x y cluster weight<Links> weight<Total link strength> weight<Documents> weight<Citations> weight<Norm. citations> score<Avg. pub. year> score<Avg. citations> score<Avg. norm. citations>
1 James 1.0551 -0.2935 2 2 98 88 4221 109.3879 1996.8409 47.9659 1.243
2 Mary 0.7492 0.2841 2 4 103 91 1994 55.0416 2011.7363 21.9121 0.6049
3 John -0.6243 -0.7247 1 4 101 89 3178 143.3831 2017.1461 35.7079 1.611
4 Linda -0.0722 0.0248 3 5 22 261 7177 209.8957 2010.2146 27.4981 0.8042
5 David 0.1026 0.4626 3 6 35 124 5843 199.8492 2010.7581 47.121 1.6117
6 Sarah -0.5883 0.3511 4 6 163 228 12930 436.0204 2013.1798 56.7105 1.9124
7 Paul -0.3409 0.7997 4 5 155 168 9850 294.1641 2012.6071 58.631 1.751
8 Karen -0.6236 -0.1752 1 5 43 181 3733 173.188 2016.3149 20.6243 0.9568
9 Daniel -0.1581 -0.5063 1 5 109 395 9382 344.7116 2014.1013 23.7519 0.8727
10 Emily 0.5004 -0.2224 2 6 185 431 13528 371.2338 2006.7889 31.3875 0.8613
The above map file can be downloaded here.
This is an example of a VOSviewer network file:
1 2 10
1 10 88
2 5 1
2 7 1
2 10 91
3 6 3
3 8 14
3 9 82
3 10 2
4 5 13
4 6 2
4 8 2
4 9 3
4 10 2
5 6 9
5 7 10
5 9 1
5 10 1
6 7 140
6 8 5
6 9 4
7 8 3
7 10 1
8 9 19
The above network file can be downloaded here.
Providing the above map and network file as input to VOSviewer Online yields the following visualization: